Odd problems

Hello all, I am a new poster. I hope I can be of help here at The 12 Volt. I hape a pretty good knowledge of all things stereo related, but these problems I'm having leave me quite confused. The Components: 1996 Chevy Blazer, 4dr., V-6, Black (car) Pioneer DEH-7400MP (head unit) 2 Pioneer 4x6 (dash speakers) (wired as front speakers) 2 Infinity Reference 5.25 (front door) (wired as rear speakers) 2 Pioneer 5.25 (rear door) (wired as rear speakers) 1 Infinity Kappa Perfec 12.1D (wired in parallel) 1 Pyramid Crystal 1000W (bridged) (not a very good amp) On order: 1 Phoenix Gold Xenon 400.1 The Setup: I have all the speakers wired into the factory wiring. The head unit uses the factory wiring. I have the RCA cables run behind the dash to the left, over the steering wheel, down the door jam(sp?), and to the back from there. I have the power wire run from the battery, to the passenger door, and underneath the car. The Problem: (1) Seems to be that every time I start my car, change CD's, or just turn the radio on, the amp goes into protect. So what I do is turn the head unit off, then on again, and it works. What the heck's up with that? (2) After about 25-30 minutes of constant listening, the amp (I'm guessing it's the amp) only puts out half power or less. (3) Kinda related to problem 2. At times I get a strange hum from my sub. When I use my brakes, it makes another strange sound. For lack of a better description, it sounds like a short fart. Seems like it only does this at night. My Hypothesis: I actually have a couple ideas, but I'm not to sure. (1) The amp is shot, which I know that it is, but that Phoenix Gold amp, I actually have installed it before, and still had problem 1 happen. Which would mean that it's actually a problem with the head unit. (2) The head unit is shot. Plain and simple. I don't like this theory. Anyways I'm gonna rip all of the amp wiring out and re-run them and see if that helps any. Doubt it will, but it needs to be done anyways. Thank you for taking the time to answer these questions in advance. Paul

you probably have a ground problem, and the head unit may not have enough current on the turn on lead, use a relay that may help

i the second the ground notion, it amazing how many problems you can have with one stupid ring connector....

I am on board with the ground issue. I would also add a relay to the remote line, just to be better safe than sorry, also I love that little click of the relay triggering the amp:)double-secret reverse-osmosis speaker-cone-induced high-level interference distortion, Its a killer

Than you for all for your relpies. When you say a ground problem, do you mead a ground problem with the head unit or the amp?? And also, for a relay, would you put that on the rempte line? Paul

Ground problem with the amplifier. If you are running the amp in mono and running it at 2 ohms, this doubles all tasks that the amp must do. Chances are that you are also asking the amp to do something that it was not designed for (this I am assuming as it is a 2 channel amp that is bridged to mono and running at 2 ohms). It most surely will send the amp into protection. Make 100% sure that you have a good ground for the amplifier.Top Secret, I can tell you but then my wife will kill me.

The amp is supposed to be 2 ohm stable. I have it grounded to the bolt that holds the backseat to the body, so that should be a pretty good ground, but if not, do you have any other reccomendations as to where to ground it?

Most 2 channel amplifiers are stable to 2 ohms stereo - this is the same as 4 ohms mono. I highly doubt that this amp is stable to 2 ohms mono. If it were then you would also have a 1 ohm stereo rating. The bolt that holds the seat in is usually a poor ground. In most GM vehicles it is best to run a ground wire direct to the battery due to the resistance on the ground return.Top Secret, I can tell you but then my wife will kill me.

WO WO WO WO WO WO WO. Rob are you telling him to run the ground for his amp strait to his battery. If you are I am going to have to whole heartedly disagree. Rule of thumb is 3 feet or less for the amp ground. If you wanna run a saftey ground thats one thing but to run the amp ground that far is Ludacris to me. I would use a wire brush on a drill and scrap the paint off a piece of double metal in the vehicle by the amp then use  self tapping screw to ground the amp. Also wouldnt hurt to reground the battery under the hood being the factory grounds usually suck.double-secret reverse-osmosis speaker-cone-induced high-level interference distortion, Its a killer